1. Field of the Invention
The present invention relates to resource virtualization. In one example, the present invention relates to methods and apparatus for efficiently providing resources such as peripheral interfaces and peripheral components in a virtualized, shared, and redundant manner to multiple servers connected over an I/O bus interface.
2. Description of Related Art
A server or computing system generally includes one or more processors, memory, and peripheral components and peripheral interfaces. Examples of peripheral components include cryptographic accelerators, graphics accelerators, and eXtensible Markup Language (XML) accelerators. Examples of peripheral interfaces include network interface cards (NIC), serial ATA (SATA) adapters, and host bus adapters (HBA). To increase processing power, servers are often aggregated as blades in a rack or as servers on a server farm or data center and interconnected using various network backbones or backplanes. In some examples, each server includes a network interface card configured for communication over an Ethernet network. The Ethernet network can include other devices that allow routing and switching to external entities and networks. To provide fault-tolerance, individual servers are often configured with redundant resources.
For example, a server may include multiple disks arranged as a redundant array of independent disks (RAID) to allow for continued operation in the event of the disk failure. Each server may also have multiple CPUs or multiple network cards to provide for fault tolerance. However, providing redundant resources in each server in a server rack or server farm can be expensive. A server farm including 40 individual systems and 40 disks would require typically in additional 40 disks for redundancy on each particular system. Redundancy can typically only be provided in a rigid and inflexible manner. A large number of links and redundant Ethernet links are needed to connect servers to networks.
Because resources such as peripheral components and peripheral interfaces are assigned on a per server or a per processor basis, other servers do not typically have access to these resources. In order to provide adequate resources for each server, resources are typically over-provisioned. That is, more hardware acceleration is provided than is typically needed. More network interface bandwidth is allocated than is typically used simply to handle worst-case or expected worst-case scenarios. Resources are over-provisioned resulting in overall waste and low utilization. Resource assignment on a per server or a per processor basis also limits the ability to reconstruct or reconfigure a resource environment. For example, XML accelerators may have to be included on each server even though each accelerator may be underutilized.
Having a number of disparate servers also increases the complexity associated with individual system management. The servers would typically have to be individually administered without the benefit of centralized administration. Oftentimes, servers would be equipped with narrowing graphics cards and I/O subsystems to allow for system administrator access.
Conventional system architectures create resource usage inefficiency, server management inefficiency, security loop holes, reconfiguration inflexibility, along with a number of other drawbacks. Consequently, it is desirable to provide techniques and mechanisms for providing virtualized resources including peripheral interfaces and peripheral components to servers in an efficient and effective manner to allow implementation of features conventionally not provided.